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All IPCC definitions taken from Climate Change 2007: The Physical Science Basis. Working Group I Contribution to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change, Annex I, Glossary, pp. 941-954. Cambridge University Press.

Posted on 30 November 2017 by Bart Verheggen

Blogs on which man-made climate change and its impacts are downplayed are far removed from the scientific literature. That is the conclusion of a new article in Bioscience in which a variety of blogs was compared with the scientific literature regarding the shrinking Arctic sea ice and the impact on polar bears.

Jeff Harvey, a Canadian ecologist working at the Netherlands Institute for Ecology (NIOO-KNAW) and the Free University of Amsterdam (VU), set out to investigate how the information on blogs relates to the scientific literature. The focus was on conclusions about Arctic sea ice and polar bears. The results have been published in the article “Internet Blogs, Polar Bears, and Climate-Change Denial by Proxy” in the journal Bioscience. Disclaimer: I’m a co-author of said article.

So what did we find? There is a clear separation amongst blogs, where approximately half of the 90 blogs investigated agree with the majority of the scientific literature, whereas other blogs took a position that is diametrically opposed to the scientific conclusions. Most of the blogs in the latter group based their opinions on one and the same source: Susan Crockford.

90 blogs and 92 scientific articles were classified according to six statements about Arctic sea ice and polar bears and the citation of Crockford. The figure shows the results of a principal component analysis (PCA) of the results. PCA is a technique to show the maximum amount of variation in a dataset with a minimum of newly defined parameters, the so-called principal components. The score on PC1 shows a separation between on the one hand the position that Arctic sea ice extent is shrinking and that this poses a threat to polar bears (most scientific articles and science-based blogs) and on the other side the position that Arctic sea ice is not shrinking or that it’s due to natural variability and that polar bears are not threatened (pseudo-skeptical blogs).

Arctic Sea ice

Arctic sea ice has shrunk dramatically in the past few decades, both in surface area and in thickness. This trend is expected to continue with ongoing global warming as a result of greenhouse gas emissions. Of course the decrease in sea ice doesn’t happen monotonically, but rather with ups and downs as a result of natural variability. When it happens to fit their perspective, such short term fluctuations are framed as a ‘recovery’ on certain blogs, or the decrease in Arctic sea ice is downplayed in other ways.

Polar bears

Polar bears depend on sea ice for catching their main prey, seals. So their habitat literally melts away as temperatures rise. Over time, polar bears have become iconic symbols of the negative effects of global warming. The population has been relatively stable so far, but you can’t just extrapolate that to the future. Biological impacts are often non-linear, and their dependence on sea ice means that in the future polar bears will likely face difficulties from continuing warming trend. Indeed, they have been classified as ‘vulnerable’ by the International Union for the Conservation of Nature (IUCN) and as ‘threatened’ under the US Endangered Species Act.

“No climate report is complete without an obligatory photo of a polar bear balancing on a piece of ice”, John Oliver said in the famous 97% episode of “Last Week Tonight”.

But what about the previous interglacial?

The polar bear species has survived the previous interglacial ~125,000 years ago. Some deduce from that that the polar bear will be fine. However, if CO2 emissions aren’t drastically reduced temperatures will get a lot warmer over the coming centuries and even millennia than during the previous interglacial. Moreover, during the previous interglacial summers were probably not completely ice-free, as is expected to happen later this century as a consequence of continuing warming (which of course depends on how global emissions evolve). The current warming trend is many times faster than back then, making potential adaptation to new conditions more difficult. Besides shrinking sea ice there are currently also other factors that negatively affect polar bears, such as human settlements, industrial activities, hunting, bio-accumulation of toxins, and smaller seal populations.

Blogs

A future with ‘business as usual’ emissions doesn’t look bright for the polar bear. Blogs appear to fall into two camps in how they write about this topic. On pseudo-skeptical blogs scientific uncertainty is twisted into ignorance, or the current situation is extrapolated into the future without taking into account the available knowledge of polar bear ecology. They usually don’t base themselves on the scientific literature, but rather on the statements of one person. These rather unfounded opinions are consequently recycled via the blogosphere, which in this respect acts as an echo-chamber. Susan Crockford writes a lot about polar bears, but does so mostly on her own website and for anti-mitigation thinktanks such as the Heartland Institute and the Global Warming Policy Foundation (GWPF); not in the scientific literature.

The gap between scientific conclusions and pseudo-skeptical blogs will not be a great surprise to those who closely follow both the scientific and the public debate about climate change. After all, this tendency is more generally visible than only on the topic of Arctic sea ice and polar bears. This is however the first time that this has been demonstrated on the basis of a systematic comparison between the scientific literature and blogs. To close the consensus gap the authors call on their fellow scientists to actively participate in the public debate.

Comments

Good article. I want to give my personal point of view on this, because I think its likely shared to some extent. The climate issue went public most strongly in the 1990s, and initially it seemed to me there was obvious evidence we were warming the climate. However I became distracted for about a year, after listening to various quite convincing sceptical points on climate change. This included material on the arctic and polar bears, and other things like theories about cosmic rays causing the warming (of course they arent). It seemed convincing, yet highly suspicious as well.

Only when I was off work sick with time on my hands, and dug deeper was it clear these sceptical points were either nonsense, or very misleading. The trouble is this takes time as "the devil is in the detail".

I see various people genuinely believing the most inane denialist rubbish, partly because they dont have the time to always cooly evaluate the fine detail or read complex rebuttals. Although its very important to make these rebuttals, and this website was one reason I saw the problems in denialist claims.

Perhaps what we ideally need is more politicians and leaders of business speaking out quite bluntly that climate denialists are talking misleading rubbish. This is an accurate assessment, so I dont see why they don't. Perhaps they are afraid of offending people, but its not freedom of speech to be making misleading sceptical claims, and quote material out of conext etc. This is an abuse of free speech.

I share your dissatisfaction that more leaders are not helping raise awareness and better inform the population. I believe the reason is the experiment with Freedom that has gone so wrong.

Leaders in business and politics act based on perceptions of Upsides and Downsides. The ease of gaining popular support for Private Interests that compromise the Public Interest of developing lasting improvements for all of humanity is the problem. There is little Upside when so many people can be so easily tempted to believe nonsense just because it suits their Private Interest in having a better time any way they can get away with.

One required change is increasing the number of people who understand that freedom is a privilege that a person earns by proving they will limit their actions and responsibly and considerately assist in developing a lasting better future for others. That would change the Upside Downside assessments of leaders, especially if it was possible to remove a leader by proving they were acting contrary to the Public Interest.

This paper smears an outstanding and eminent scientist in the field of Arctic Fauna. Susan Crockford probably knows more about the survival of all forms of Arctic mamalian species than anybody else. I am sure the following list of her papers won't make it through your moderation however I will give it a try:

**Crockford, S.J. 2012. Directionality in polar bear hybridization. Comment, with references (May 1) to Edwards et al. 2011. “Ancient hybridization and an Irish origin for the modern polar bear matriline.” Current Biology 21:1251-1258. to view comments, go through the host website, http://www.Cell.com and find the paper at the Current Biology website. http://www.cell.com/current-biology/abstract/S0960-9822%2811%2900645-2#Comments

Ovodov, N.D., Crockford, S.J., Kuzmin, Y.V., Higham, T.F.G., Hodgins, G.W.L. and van der Plicht, J.. 2011. A 33,000 year old incipient dog from the Altai Mountains of Siberia: Evidence of the earliest domestication disrupted by the Last Glacial Maximum. PLoS One 10.1371/journal.pone.0022821. http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0022821

Crockford, S.J., 2005. Breeds of native dogs in North America before the arrival of European dogs. Proceedings of the World Small Animal Veterinary Congress, Mexico City. [invited lecture] available online at: http://www.vin.com/proceedings/Proceedings.plx?CID=WSAVA2005&PID=11071&O=Generic

Thank you for the list. Looking it over I see that Susan Crockford has not written any peer reviewed articles on polar bears or their biology. She made two comments on others work on polar bear genetics. The majority of her work appears to be on domestic dogs. There is some material on archaeology and fossil animals.

MatthewL @4 , as M. Sweet mentions — possibly you have not noticed it, but of those 29 scientific papers you mention, hardly any of them seem to be dealing with modern-day polar bear numbers (or, far more importantly, with the state of health of polar bear populations).

Polar bear numbers are notoriously difficult to assess accurately. Surveys suggest that numbers are growing in one region and static/declining in other regions. Part of the inaccuracy stems from the mobility of bears, and from the lack of volunteers "to bell the cat" with transponder collars. (The reason for the volunteer lack is unknown.)

What can be said for most populations (of any animals) in the wild, is that the biggest threat to them is loss of habitat. And considerable habitat loss is occurring for the polar bears. It would be a bold scientist indeed who would assert that the future looks tolerably good for polar bears particularly. And particularly worse for polar bears too, is that they are highly adapted to a rather specialised diet & annual cycle of feeding — and are far less omnivorous than their ursine relatives. So it's not looking good.

Worse again, some surveys report (as best as can be judged from a safe distance!) that there has been a decline in polar bear body weight. Even without a drop in absolute numbers as yet, this could indicate the approach of a sudden "crash" — which won't be verified until after it has happened.

Then we come to the reasons for Dr Crockford to be such an outlier in her opinions. The reek of Heartland Institute is strong.

Not to mention her anti-science attitude about climate change itself. (Never a good look, in the assessing of someone's objectivity in matters scientific.)

She has done meta-analysis on research data on polar bear numbers which is compelling, if not peer reviewed. As a medic I am well aware of the problems with peer review and the lack of replicated results, so I do not dismiss any paper just because it is not peer reviewed.

There is nothing to suggest that global numbers of polar bears have declined in the last 40 years and plenty to suggest that they have grown. It may be difficult to disentangle growth due to a reduction in hunting with decline due to a reduction in habitat. However, to date, the former effect has evidently been stronger than the latter, despite a steady decline in Arctic sea ice. You are disingenous in your statement that polar bears are listed as endangered. This was done to protect them from dangerous men with dangerous guns, not gradual sea ice decline.

From what I can gather, most of the time when an unbiased assesment is done on Arctic fauna the results tend to be less alarming than the initial press would suggest. For instance the recent Fish and Wildlife Service assesment of walrus populations as not endangered following "analysis of the best available scientific information".

https://www.fws.gov/alaska/fisheries/mmm/walrus/esa.htm

I do not know of Crockford's attitude on climate change, but as she is a highly qualified and published scientist who has worked extensively in the Arctic I very much doubt it is "anti-science" - any more than Judith Curry, Pielke Junior and Roy Spencer are "anti-science" or "deniers" (absolutely hate the use of that word). They are all highly qualified scientists in relevant fields of study who understand global warming and greenhouse gases but have come to a different view of the scientific evidence than taken on this blog - largely through empircal study and analysis rather than reliance on the wildly variable reuslts from General Circulation Models.

I am broadly on your side, fascinated by the science, but absolutely despair of the politics on both sides. The rampant and totally ludicrous millenial cult level alarmism (Manhatten under water by 2010, no Arctic ice by 2012, 5 million climate refugees by 2015 etc) in the press followed by ridiculous self justification and cognitive dissonance when the world does not end ("its worse than we thought!") just demolishes credibility . As for the "sky dragon slayers", I absolutely despair...

Blogs really are not the problem. The problem is that the uncertainties in the science are so huge (ECS between 1.5C and 4C per CO2 doubling according to IPCC) that it is quite possible to take a reasonable view at both ends of the spectrum. It would be better for sites such as this to climb down from the moral high ground and start looking at the effect that crying "wolf!" so often has on scientific credibility when the wolf does not appear.

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Moderator Response:

[JH] You are now skating on the thin ice of sloganeering which is prohibited by the SkS Comments Policy.

Please note that posting comments here at SkS is a privilege, not a right. This privilege can be rescinded if the posting individual treats adherence to the Comments Policy as optional, rather than the mandatory condition of participating in this online forum.

Please take the time to review the policy and ensure future comments are in full compliance with it. Thanks for your understanding and compliance in this matter.

As lead author of the Bioscience paper I will make three responses to Matthew L’s erroneous posts. First, our paper is about scientific ethics, not about Susan Crockford, and we set out to prove that blogs which deny AGW largely ignore the primary scientific literature. We proved that here using PCA. Polar bears are used as biotic proxies for AGW by climate change deniers, hence why we focused on these iconic mammals. In truth, the empirical literature is filled with studies showing the harmful effects of warming on soil, aboveground terrestrial and aquatic communities. This wealth of data is ignored by denier blogs because it would be impossible for them to counter this veritable tsunami of data. Moreover, since blogs are operated usually by people lacking formal training in the relevant fields, a deliberate attempt is made to focus on only a tiny subset of areas or fields.

Second, Susan Crockford has only 17 papers in her career on the ISI Web of Science (none since 2014); her work has been cited less than 200 times and her h-factor is 7. Moreover, she has conducted no primary research on polar bear biology or ecology. On this basis I would question whether she is an ‘outstanding and eminent scientist in the field of Arctic fauna’. To argue that she knows more about the survival of Arctic fauna than anyone else is absurd. Three of my co-authors, Steven Amstrup, Ian Stirling and Eric Post, by contrast, have a combined total of over 500 publications, 15,000 citations and vastly more expertise on Arctic ecology than Crockford.

Third, there are not two sides in discussions about AGW. There is one side whose conclusions are supported by the vast majority of the empirical data and another side whose arguments are not. Of course there are uncertainties over future projections of AGW, and deniers exploit these as much as possible to sow doubt. But there are many certainties as well, and scientists need to do a better job getting these across to the general public. Oreskes and Conway named their book, ‘Merchants of Doubt’ for a reason. Deniers will never win scientific debates, but that is not their aim. Their aim is to convince the public that the science is not settled. In tis way nothing will be done to mitigate greenhouse gas emissions.

"The problem is that the uncertainties in the science are so huge (ECS between 1.5C and 4C per CO2 doubling according to IPCC) that it is quite possible to take a reasonable view at both ends of the spectrum. "

With respect this doesn't make too much sense. You cannot take a reasonable view at extreme ends of the spectrum, because that Sir is a contradiction in terms. A reasonable view in general terms is a rational and / or middle ground view.

Most research finds that climate sensitivity is moderate to high. A reasonable view is to take at least the centre ground and say climate sensitivity is at least moderate.

I think you could go further on the basis of published science, and also say it is likely to be moderate, could be high, and is unlikely to be low. Anything else that favours one end of the spectrum would be your opinion and personal bias on what end you favour.

Please also note the low sensitivity papers have also been heavily criticised, and recent temperaturess bring their methodology and findings further into question.

"(2) Matthew's comment is factualy correct — not "misinformation." From this information Bart and Michael draw different *conclusions* about the relevance of her training and experience."

Nobody said her publishing record is missinformation, you are making a straw man argument. Its her views and findings that are questioned.

And yes they do draw different conclusions, but only one conclusion makes sense, namely M Sweets. Susan Crockfords research is broadly speaking in zoology, with nothing published in the peer reviewed literature on polar bears apart from some very brief comment piece, and almost nothing published related to climate change. Thefore its nonsensical for anyone to consider her an expert or authority on polar bears, and relation to climate change.

If you want to be an expert and taken seriously, you have to prove it to your peers, and the only convincing way is to publish research of substance specifically on polar bears, or do a Phd thesis on polar bears, otherwise claims of expertise are empty assertions, like some arm chair retired physics teacher claiming to be a leading expert on black holes on the basis of some blog post he wrote. No, an expert is someonelike S Hawking, who has offered some substantial proof he is an expert. Its no different for Susan Crockford.

Just my view on polar bears, fwiw. Briefly I think polar bears are in trouble from declining sea ice. Polar bears use the floating sea ice, and sea ice is also important to seal populations, on which polar bears depend.

There is mixed evidence of whether polar bear numbers are declining overall right now because of so many influences, measuring accuracy, climate issues and hunting. But there is good evidence of declining populations of some seals here.

This is not rocket science. Species have some level of adaptability. Polar bears are probably still finding enough seals to get by. But in 20 years impacts will be much greater in terms of declining sea ice and seal numbers, and will stretch adaptability of polar bears. If seal populations declining now as seems apparent in at least some cases as above, directly from declining sea ice, they can only decine further. This is likely to impact on polar bears given its their food supply, and it's over a relatively short time frame of decades to a century. This is short in adaptation and evolutionary terms.

The issue is one where its too early to get a clear picture on polar bears partly because of changes in hunting, and its the projections that count most. Any 'reasonable' consideration paints a grim future for polar bears later this century.

Seems to me that the gist of the piece is that polar bear numbers are a sort of proxy for temperatures.

Don't they call this a gish-gallop? Starting and then continuing an argument based on animal numbers is so far from having any conclusions - at least until centuries have passed - is merely a distraction. Her scientific credentials don't even enter into it.

"This paper smears an outstanding and eminent scientist in the field of Arctic Fauna."

The evidence he provided showed that Susan Crockford has never studied any living fauna in the Arctic. She has several papers on dogs and a few on archaelogical research in the Arctic. His statement "outstanding and eminent" has been shown to be false and therefor is misinformation.

Jeffh describes Steven Amstrup, Ian Stirling and Eric Post, researchers who are "outstanding and eminent". They have 1000 times more citations about arctic fauna than Susan Crockford. Since Susan Crockford has never observed fauna in the arctic, these researchers have an infinite more experience in the field than she does.

Quite right, FMeditor @ 13 et seq . . . CBDunkerson should more properly have used the term "disinformation" (rather than "misinformation").

I suppose MatthewL could tell us whether his source was Dr Crockford's blogsite or Mr Kummer's blogsite — but really the exact source of the disinformation is of little relevance to the basic question.

On Kummer's blogsite, as far as I have seen, the topics tend toward the partisan-political, by himself and subsidiary authors. The climate science denialism seems to be a minor personal side-issue for him. Nevertheless, Kummer doesn't hesitate to have his climate article (on polar bears & Crockford) bristling with non-sequiturs & other disinformation (e.g. the link to Crockford's publication list . . . thereby implying to the casual/superficial reader, that Crockford was an expert in the field and whose opinion was worthy of respect).

It appears that Crockford's expertise on the evolution of the polar bears . . . is about as relevant to today, as the evolution of the rhinoceros is to the current problems of the rhinoceros. Worse, Crockford's own apologism (against climate science) on her own blogsite shows the cherry-picking [Hudson Bay bears] and logical non-sequiturs, irresponsible risk-management & short-term thinking so typically unobjective and in short:unscientific.

Jeff H. Please name the "deniers" you are referring to. The three names I put forward stress repeatedly that they fully buy into greenhouse gas global warming. However they do not agree with the established view that it is as rapid or likely to be as catastrophic as most articles on sites such as this. They put forward reasonable arguments and are far from extreme. So far the worst predictions of imminent catastrophe have failed to materialise. The longer the ice in the Arctic fails to melt away, the polar bears thrive, coral atols fail to sink and agricultural yields continue to grow the more convincing their arguments become and the less convincing are the predictions of disaster by the end of the century. I am still worried that the worst might happen and still read the science but am a lot less worried than I was 20 years ago when so many predictions of doom were made that have failed to come to pass. I notice you failed to respond to my comment on the tendancy towards self justification, and cognitive dissonance in the scientific community when predictions fail. Ever read the book "Mistakes were made (but not by me)"? I think you should. When you cry "wolf!" and predict catastrophe you had befter be very certain it will happen or you are not to lose all credibility. Professor Peter Wadhams was once a despected scientist...

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(1) "The climate science denialism seems to be a minor personal side-issue for him."

I don't respond to unsupported smears, but in this case will point out that I am a strong — even dogmatic — supporter of the IPCC and major climate agencies (esp NOAA). Their work is the foundation of my posts. That you consider that "denialism" is ... strange, and sad.

(2) "the topics tend toward the partisan-political,"

The tagline of the FM website says it is about "geopolics." So, yes, there is a lot about politics. Much of our content attacks extremists on both Left and Right. That's the case for posts about the policy debate about climate change — where both extremes have turned against the IPCC.

(3) "thereby implying to the casual/superficial reader, that Crockford was an expert in the field and whose opinion was worthy of respect)."

Your description of that section of the post is misleading. As is the standard practice on the FM website, we provide readers with full information so that they can make the own evaluation. I gave a summary of her professional background — education, a link to her publication (including her paper about polar bears), etc.

Calling that "disinformation" is daft.

Here background in zoology is relevant to this subject. Time will tell if her analysis is correct. As Popper said (paraphrasing), successful predictions are the gold standard in science.

FMeditor @25 , you cherry-pick a couple of "failed" comments [2007 Prof X said: Arctic summers ice-free by 2013 . . . Also 2002 Prof Y said: Regular summer trade ships within a decade] to imply that all of mainstream climate science is worthless. And then you cherry-pick summer polar sea-ice extents in 2008 and 2017 . . . while turning a blind eye [= not informing your readers] to the multi-year trend while at the same time ignoring the spectacularly-large decline in summer polar sea-ice volume ; and all the associated causations of these effects [i.e. ongoing AGW]. And then another non-sequitur : you imply that Dr Crockford's PhD in zoology would/could qualify her as a new C.R.Darwin or S.J.Gould or someone of similar weighty opinion.

FMeditor, your article was worthy of the British Daily Mail. What next : Al Gore said New York would be 20 feet under water by now?!?

You have a strange way of being "a strong — even dogmatic — supporter of the IPCC and major climate agencies". Hmm, with friends like you, why would science need enemies? ;-)

On the FabiusMaximus politics, I am eclectic. Some I agree with, and some I think are "unsupported". And I also perceive that the Shakespearean Lady protests too much, about the FM lack of bias. # But all this is irrelevant to the outlier position of Dr Crockford and her lack of objectivity.

"Full information" given on the FM website? Far from it, on Crockford/AGW. Half-truths may be presented as disinformation, or OTOH may be presented in a way that is truthful & useful to the reader. It's largely the editor's choice, don't you think?

As Popper would say if alive today : the mainstream scientists have done a fine job in gathering the climate science evidence of rapid Anthropogenic Global Warming, and their predictions so far have been good . . . while the predictions (and science) by Lindzen & other "contrarians" have been appallingly bad.

He says this despite indisputable evidence from multiple sources of a longer term decline in arctic sea ice areas and thickness. He must either dispute the obvious, or live in a world shielded from actual evidence like this. Either way, this is why we call you people 'denialists'.

The things we wanted to emphasize in our paper are important concepts like tipping points, critical threshold, time lags and what Tilman and May referred to as the ‘extinction debt’ in their 1994 Nature article. Polar bears depend on habitat that literally melts as temperatures rise. If, as projected, ice extent in the Arctic continues to decline, then at some point bear populations WILL collapse. We have seen similar occurrences in tropical biota; species remained in fairly sizeable numbers until forest cover was reduced below a critical threshold and then numbers plummeted, often so rapidly that extinction was inevitable.

We therefore emphasize that focusing on today tells us little about future projections in a warming world. Paul Ehrlich’s building analogy is appropriate here. A man jumps off the top of a 100 story building, plummets 50 floors and while doing so shouts “everything is OK!”. Well, it clearly isn’t OK. Climate change skeptics and deniers routinely fail or refuse to project. Their mantra is, “everything is OK today, so don’t worry about tomorrow”. This isn’t science. I was taught as a professional ecologist to place the demographics of species and species populations in a dynamic, changing world. The world is not static. Humans are altering vast swathes of the biosphere, including surface temperatures, at rates well beyond the capacity of many species to adapt. Therein lies the rub.

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Moderator Response:

[PS] By the way, thanks Jeff for stopping by and entering this discussion. It is appreciated.

In addition to the threat to polar bear populations from reduced Arctic sea ice extents, there is already the challenge to polar bear populations due to the later formation of sea ice. I have seen numerous reports of polar bears trying to survive on the shorelines because of later formation of sea ice. unlike humans who can get a science based forecast and plan accordingly, polar bears base what they do on what they are accustomed to.

Unfortunately many humans fail to 'learn from science' and will not change their behavior responsibly if the required change is contrary to what they have developed a desire for ... become addicted to.

Yes polar bears are accustomed to a certain way of life. It's not as if polar bears and seals can build boats. Polar bears eat seals and also carcasses of beluga whales. But seal numbers are declining, and arctic belguga whale numbers are under threat from hunting:

Polar bears are not evolved to eat smaller fish easily. Its hard for me to see how they can adapt in time to all these changing circumstances. Things will reach a tipping point where numbers dwindle at an accelerating rate, and even finding a mate will become more difficult.

The resilent or adaptable species tend to be insects, bacteria and smaller mammals. And humans to an extent. But our vulnerability is the complexity of our economy and society now.

I had mentioned Mr Larry Kummer's blogsite "Fabius Maximus" as an example of the "denier" blogs alluded to by the OP — blogs which opposed the overwhelming scientific evidence of AGW and which inter alia tended to make use of a lone outlier scientist [in this particular case, Dr Susan Crockford] for the purpose of "proxy-style denialism" of the global problems produced by AGW.

A quick look over "Fabius Maximus" (a blog with Headline Mission of opposing the modern degeneracy of the American Nation) . . . showed me that the blogsite was mostly political in nature, with little attention to science. The link from Dr Crockford to a recent "Fabius Maximus" article by Mr Kummer, showed a standard denialist article with misrepresentations & poor logic. Standard fare, indeed — yet in presence of the other generally political articles in the blog, I drew the conclusion that the science denialism was "a minor personal side-issue for him [as prime author of the blog]".

How wrong I was.

Mr Kummer's subsequent (post #25) assertion that he was no denier but "a strong supporter" of the IPCC and major climate agencies . . . was surprising to me, for it showed a vast discordance with the body of his article. A discordance of truly Presidential degree (an allusion to the current President, of course).

Digging deeper, I found quite a number of Kummer articles with strong science-denying bias [here I could have said climate-science-denying — but all well-established science hangs together, so to speak . . . and so to be a denier of one area is in effect to be a denier of all areas].

There were also querulous posts by Mr Kummer (to similar effect) on third-party blogs. #So I was quite wrong to describe him as a minor or low-grade "denier". He actually rates as a red-hot public denier of climate science.

The irony of this, is that his blog which is nominally fighting the decline/degeneracy of "the nation" . . . is actually an active contributor to the anti-science movement which is a causative part of the national decline.

I perused through Matthew L's list of Crockford's publications. I followed the link to the two Comments posted with respect to journal papers.

The first comment (on the Science paper) discussed observations of cross-breeding between brown bears and polar bears, and says nothing about climate change or future directions of polar bear habitat reductions. I can't tell from the web page whether the comment is strictly an on-line comment or whether itt appeared in print. (The paper is from 2012.)

The second link (to the Current Biology paper) is also a paper about historical brown bear and polar bear hybridization, but I see no comments listed at all. Using that web page's search tool produced no material written by Susan Crockford. The paper is from 2011.

It is interesting to note that in the first comment, Susan Crockford lists her affiliation as "Department of Anthropology ... University of Victoria". The department's faculty listing states that she is an Adjunct Assistant Professor. Being an adjunct carries a lot less weight than being a university employee.

Desmog.ca also has a story on this paper, which includes an interview with one of the authors of the paper - Ian Stirling. I've met him ,and he is a real polar bear expert. His opinion of Susan Crockford, expressed in the story, is not flattering.

Some people probably consider Crockfords views have "truthiness" because they tell people what they want to hear, and are consistent with their world view, therefore she is an "expert". I think that's how it works. Expertise as normally and properly defined doesn't even enter into it.

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